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Journal Cover Reactive and Functional Polymers
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   Hybrid Journal Hybrid journal (It can contain Open Access articles)
   ISSN (Print) 1381-5148
   Published by Elsevier Homepage  [3043 journals]
  • Biocompatible waterborne polyurethane-urea elastomer as intelligent
           anticancer drug release matrix: A sustained drug release study
    • Authors: Ali Bahadur; Aamer Saeed; Shahid Iqbal; Muhammad Shoaib; Muhammad Saif ur Rahman; Muhammad Imran Bashir; Muhammad Asghar; Muhammad Asif Ali; Tahir Mahmood
      Pages: 57 - 63
      Abstract: Publication date: October 2017
      Source:Reactive and Functional Polymers, Volume 119
      Author(s): Ali Bahadur, Aamer Saeed, Shahid Iqbal, Muhammad Shoaib, Muhammad Saif ur Rahman, Muhammad Imran Bashir, Muhammad Asghar, Muhammad Asif Ali, Tahir Mahmood
      Waterborne biodegradable polyurethane–urea (WPUU) elastomer is a revolutionary step in the field of green polymer chemistry. In the present study, emulsifier–free biodegradable WPUU elastomer was synthesized by using lysine as an internal emulsifier as well as a chain extender. WPUU elastomer was used as the stimuli–responsive drug release matrix, loaded by cisplatin as a model anticancer drug. Sustained drug release was studied by changing pH (4.4–7.4), drug release medium, and NCO/OH ratio (3–4). Furthermore, significantly inhibitory effect against Sw–620 cancer lines was observed. Highest cumulative drug release of 71.9% was observed at pH of 7.4 in phosphate buffer saline (PBS) by the system having NCO/OH=3 for 250h. The oxidative degradation was evaluated in CoCl2/H2O2 solution. Mechanical properties were tested by using the mechanical testing machine. The synthesized WPUU films exhibited high thermal stability, hardness, tensile strength and hydrophobicity.
      Graphical abstract image

      PubDate: 2017-09-02T16:13:50Z
      DOI: 10.1016/j.reactfunctpolym.2017.08.001
      Issue No: Vol. 119 (2017)
  • Hydrazone cross-linked micelles based on redox degradable block copolymer
           for enhanced stability and controlled drug release
    • Authors: Di Xiong; Ran Zhang; Wenji Luo; Huawei Gu; Shiyuan Peng; Lijuan Zhang
      Pages: 64 - 74
      Abstract: Publication date: October 2017
      Source:Reactive and Functional Polymers, Volume 119
      Author(s): Di Xiong, Ran Zhang, Wenji Luo, Huawei Gu, Shiyuan Peng, Lijuan Zhang
      In this work, an amphiphilic copolymer, PCL-SS-P(PEGMA-co-MAEBA), which contained a disulfide joint in backbone was designed and synthesized. The subsequent micelles that self-assembled from the copolymers were cross-linked by hydrazone, resulting in novel stimuli-responsive degradable micelles with a reversible cross-linked shell. By way of the hydrazone cross-linking of the micellar shell, SCMs owned a good stability against the extensive dilution by water or organic solvent. Doxorubicin (DOX) was used as the model drug for studying the in vitro release profiles of the SCMs. In normal physiological conditions at pH7.4, a quite slow speed was observed with DOX release (only 23% after 72h); when conditions were changed to pH5.0, the SCMs successfully de-crosslinked, DOX release was accelerated (62%). Moreover, drug release was further promoted and reached 87% when 10mM GSH was present, which was primarily due to the breakage of the disulfide joint. The intracellular uptake assay proved that DOX from DOX-loaded SCMs could be efficiently delivered into HepG2 cells after 12h incubation. MTT assays confirmed that DOX-loaded SCMs owned a high cytotoxicity against HepG2 cells. These redox-responsive, degradable SCMs could be a potential candidate for efficient insoluble anticancer drug delivery and therapy.

      PubDate: 2017-09-02T16:13:50Z
      DOI: 10.1016/j.reactfunctpolym.2017.08.003
      Issue No: Vol. 119 (2017)
  • Understanding the mechanism for building woven fabrics with wettability
           ranging from superhydrophobic to superamphiphobic via an aqueous process
    • Authors: Yuanyuan Tu; Hailiang Zou; Shudong Lin; Jiwen Hu
      Pages: 75 - 81
      Abstract: Publication date: October 2017
      Source:Reactive and Functional Polymers, Volume 119
      Author(s): Yuanyuan Tu, Hailiang Zou, Shudong Lin, Jiwen Hu
      We have recently developed a novel and simple approach based on aqueous solutions of block copolymer micelles for the construction of WFs with wettability ranging from the superhydrophobic to the superamphiphobic regime. That is, the copolymers were initially dispersed into water to yield a micelle solution with the insoluble fluorinated block serving as the micellar core and the water soluble block as the micellar corona. The polyethylene terephthalate (PET) or cotton WFs were then dipped into a copolymer micelle solution and then naturally dried at room temperature before they were cured at high temperature to yield WFs with various degrees of liquid repellency. Further investigation on the mechanism for the formation of either superhydrophobic or superamphiphobic WFs using this aqueous process would facilitate the commercial applications of these water-based coatings. In this contribution, polyethylene terephthalate (PET) films with different liquid repellencies based on copolymer aqueous micelle solutions were prepared via previously reported process, and AFM and XPS techniques were respectively employed to evaluate the morphology and chemical composition of the copolymer-coated PET films. The dependence of water and oil contact angles of PET films on the concentrations of the copolymer micelle solution were evaluated and further employed for the prediction different liquid repellencies of PET WFs. The mechanism for the formation of the superhydrophobic WFs or superamphiphobic WFs was also proposed.
      Graphical abstract image

      PubDate: 2017-09-02T16:13:50Z
      DOI: 10.1016/j.reactfunctpolym.2017.08.004
      Issue No: Vol. 119 (2017)
  • Catalytic demethylation of organosolv lignin in aqueous medium using
           indium triflate under microwave irradiation
    • Authors: Jacob Podschun; Bodo Saake; Ralph Lehnen
      Pages: 82 - 86
      Abstract: Publication date: October 2017
      Source:Reactive and Functional Polymers, Volume 119
      Author(s): Jacob Podschun, Bodo Saake, Ralph Lehnen
      The anticipated shortage and price increase of fossil resources rendered material applications of renewable resources especially lignocellulosics highly attractive. When using lignin for polymeric materials, the macromolecular nature of lignin can be retained to reduce synthesis efforts. However, the effective integration of lignin into polymers is often lacking a sufficient number of reactive sites. Here, we present a method for the demethylation of lignin using the water-tolerant Lewis acid indium triflate, and compared conventional heating to a microwave-assisted approach. By appropriate dissolution of the organosolv lignin, char formation could be eliminated, and the reaction could be improved using microwave irradiation. The products were characterized by 1H, 13C and 31P NMR spectroscopy as well as size exclusion chromatography. An increase in the number of aromatic hydroxyl groups from 2.1 to 4.4mmolg−1 was obtained pointing towards enhanced suitability in application as polymeric precursor for materials such as phenolic and epoxy resins as well as polyurethanes.
      Graphical abstract image

      PubDate: 2017-09-02T16:13:50Z
      DOI: 10.1016/j.reactfunctpolym.2017.08.007
      Issue No: Vol. 119 (2017)
  • Synthesis and characterization of β-cyclodextrin nanosponges for
           N,N-diethyl-meta-toluamide complexation and their application on polyester
    • Authors: R. Peila; P. Scordino; D.B. Shanko; F. Caldera; F. Trotta; A. Ferri
      Pages: 87 - 94
      Abstract: Publication date: October 2017
      Source:Reactive and Functional Polymers, Volume 119
      Author(s): R. Peila, P. Scordino, D.B. Shanko, F. Caldera, F. Trotta, A. Ferri
      β-Cyclodextrin polymer, namely nanosponges (NSs), were synthesized using two cross-linkers: 1,1′-carbonyldiimidazole (CDI) and pyromellitic dianhydride (PMDA). The synthesized NSs were complexed with N,N-diethyl-meta-toluamide (DEET) and, after complex characterization, the NSs cross-linked with CDI were found more effective than those cross-linked with PMDA in terms of encapsulation efficiency and loading capacity. The CDI-NSs were dispersed in a polyacrylic resin, which was thermally polymerized on a polyester fabric surface. The fabric functionalization was evaluated through quantification of DEET extracted from the polyester fabrics, before and after three washing cycles. The results showed that encapsulation into NSs prolongs the persistence of DEET on polyester fabrics.

      PubDate: 2017-09-02T16:13:50Z
      DOI: 10.1016/j.reactfunctpolym.2017.08.008
      Issue No: Vol. 119 (2017)
  • Superhydrophobic polyaniline/polystyrene micro/nanostructures as
           anticorrosion coatings
    • Authors: Yunyan Zhao; Cuijuan Xing; Zhiming Zhang; Liangmin Yu
      Pages: 95 - 104
      Abstract: Publication date: October 2017
      Source:Reactive and Functional Polymers, Volume 119
      Author(s): Yunyan Zhao, Cuijuan Xing, Zhiming Zhang, Liangmin Yu
      In this paper, superhydrophobic polyaniline (PANI)/polystyrene (PS) micro/nanostructures were prepared by an electrospinning combining with drop-cast strategy for protecting carbon steel. The corrosion resistance ability and durance property of the resultant PANI/PS micro/nanostructures in 0.1M H2SO4 were investigated and compared using electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization technique. It is found out that effective anticorrosion performance can be provided by PANI/PS micro/nanostructures for carbon steel, and the corrosion protection efficiency (η) increases along with the water repellency of the PANI/PS micro/nanostructures. The protection properties of PANI/PS micro/nanostructures increased along with their water repellency. The PANI-PFOA/PS micro/nanostructures has the water contact angle value as high as 153°, demonstrating the most excellent anticorrosion properties with a promising anticorrosion efficiency of 99.48%.

      PubDate: 2017-09-02T16:13:50Z
      DOI: 10.1016/j.reactfunctpolym.2017.08.005
      Issue No: Vol. 119 (2017)
  • Rapid fabrication of electrohydrodynamic micro-/nanostructures with high
           aspect ratio using a leaky dielectric photoresist
    • Authors: Guowei Lv; Shihu Zhang; Jinyou Shao; Guolong Wang; Hongmiao Tian; Demei Yu
      Pages: 1 - 9
      Abstract: Publication date: September 2017
      Source:Reactive and Functional Polymers, Volume 118
      Author(s): Guowei Lv, Shihu Zhang, Jinyou Shao, Guolong Wang, Hongmiao Tian, Demei Yu
      A leaky dielectric photoresist was designed and prepared for rapid fabrication of high-aspect-ratio micro-/nanostructures via electrohydrodynamic patterning (EHDP). The rheological behavior and electrical properties of the photoresists were systematically investigated, since the structure formation in EHDP essentially originates from the flow and deformation of the polymeric film actuated by an applied electric field. It is found that the photoresists exhibit the suitable rheological behavior with a low viscosity of 2.4–157.7mPas, controllable electrical conductivity of 5.0×10−6 −7.2×10−4 Sm−1, as well as high homogeneity, minor surface tension of about 30 mN·m−1, favorable wettability and film-forming property on substrate and an extremely large reduction in the contact angle (down to 1.64°) of electrowetting on dielectric (EWOD). The EHDP results have shown that a higher electrical conductivity of the photoresists can lead to a higher filling height, a smaller characteristic wavelength and a shorter patterning time, while a lower viscosity can also lead to a shorter patterning time, which is accordance with the theoretical prediction. In addition, the patterning time of the photoresists cannot be too short because the following rapid ripening and coalescence of the formed microstructure will damage the high fidelity of the final pillar arrays.
      Graphical abstract image

      PubDate: 2017-07-02T13:50:24Z
      DOI: 10.1016/j.reactfunctpolym.2017.06.014
      Issue No: Vol. 118 (2017)
  • Fabrication of block copolymer templates by using dually responsive
           photoresist bottom layers
    • Authors: Kyoungok Jung; Chang Hong Bak; Se Jin Ku; Jin-Baek Kim
      Pages: 20 - 25
      Abstract: Publication date: September 2017
      Source:Reactive and Functional Polymers, Volume 118
      Author(s): Kyoungok Jung, Chang Hong Bak, Se Jin Ku, Jin-Baek Kim
      A simple and novel method was developed to fabricate a nanoporous template by using a bilayer system composed of a silicon-containing block copolymer top layer and a dually responsive photoresist bottom layer. The dually responsive bottom layer became cross-linked by heating. The cross-linked polymer was mechanically hard and insoluble in common solvents. The block copolymer pattern was transferred to the bottom layer by oxygen reactive ion etching. High-aspect-ratio nanopore arrays were generated. The cross-linked bottom layer became soluble again by chain scission upon exposure to UV light. Therefore, the template with a highly orientated array of cylindrical nanopores could be easily removed by dipping in an aqueous base solution. This versatile template of nanoporous structures could be used to create freestanding 1D nanostructures of a variety of functional materials.

      PubDate: 2017-07-12T15:34:41Z
      DOI: 10.1016/j.reactfunctpolym.2017.07.001
      Issue No: Vol. 118 (2017)
  • Applications of zwitterionic polymers
    • Authors: Liuchun Zheng; Harihara S. Sundaram; Zhiyong Wei; Chuncheng Li; Zhefan Yuan
      Pages: 51 - 61
      Abstract: Publication date: September 2017
      Source:Reactive and Functional Polymers, Volume 118
      Author(s): Liuchun Zheng, Harihara S. Sundaram, Zhiyong Wei, Chuncheng Li, Zhefan Yuan
      Zwitterionic polymers are characterized with equal anion and cation groups on the molecular chains, which make them highly hydrophilic and antifouling. They can resist nonspecific protein adsorption, bacterial adhesion, and biofilm formation. Therefore, they have great potential to be applied in a wide range of biological and medical related fields, such as antifouling coatings of biomedical implants, blood contacted sensor and drug delivery in vivo, separation membrane and marine coatings. The review mainly focuses on the progress of those applications of zwitterionic polymers on the molecular level. Problems existed in these applications are also discussed and the development of in future is prospected.

      PubDate: 2017-08-03T16:40:31Z
      DOI: 10.1016/j.reactfunctpolym.2017.07.006
      Issue No: Vol. 118 (2017)
  • Synthesis and optoelectronic properties of polymers possessing
           thieno[2,3-b]thiophene fused rings
    • Abstract: Publication date: Available online 13 October 2017
      Source:Reactive and Functional Polymers
      Author(s): M. Emin Cinar, Sule Taskiran Cankaya, Asli Capan, Mehmet S. Eroglu, Turan Ozturk
      Synthesis of novel thieno[2,3-b]thiophenes (TTs) possessing para substituted phenyl groups (pH−, MeOPh−, BrPh−, NO2Ph−, NH2Ph− and NMe2Ph−) at C-3 has been achieved through ring closure reactions of mono ketones, i.e. 1-aryl-2-(thiophen-2-ylthio)ethan-1-one, and polymerizations of TTs (PhTT (10), p-MeOPhTT (11), p-NO2PhTT (13) and p-NMe2PhTT (18)) under Suzuki coupling condition are demonstrated. The optical and electronic properties of the polymers were investigated systematically. Polymers demonstrated bathochromic shift with respect to their monomers in UV-Vis investigations up to 203nm for 23 consisting of NO2 unit. While unsubstituted phenyl possessing polymer has the smallest band gap of 2.18eV, the largest one was noticed to be 2.65eV for NMe2 containing polymer 24. Electrochemical studies revealed the relatively low oxidation potentials recorded between 1.10 and 1.31V.

      PubDate: 2017-10-13T22:26:00Z
  • Influence of backbone structure, conversion and phenolic co-curing of
           cyanate esters on side relaxations, fracture toughness, flammability
           properties and water uptake and toughening with low molecular weight
    • Abstract: Publication date: Available online 12 October 2017
      Source:Reactive and Functional Polymers
      Author(s): Christoph Uhlig, Monika Bauer, Jörg Bauer, Olaf Kahle, Ambrose C. Taylor, Anthony J. Kinloch
      The effect of backbone structure and conversion of polycyanurate networks on solid state properties has been studied and compared to co-curing with bisphenol-A. Dynamic mechanical behaviour, density, flammability properties, fracture toughness and long-term water uptake were investigated. The intensity of the γ-relaxation increases, room temperature density decreases with increasing conversion, both due to increasing free volume with increasing conversion. A brittle-ductile transition was detected by precise fracture toughness measurements; above a critical conversion the fracture toughness rises suddenly from extremely low values to a plateau or maximum: Networks with higher toughness show a maximum, those with lower toughness a plateau. Bisphenol-A modification causes intrinsic toughness variations. Toughening of two different cyanate esters with polyethersulphones synthesized with various molecular weights between 3000 and 10,500 (Mn) was investigated. Significant toughening effects can be achieved already with intermediate molecular weights lower than those of commercially-available high-Tg amorphous thermoplastics. Long-term water uptake measurements at 28°C, 50°C and 70°C over two years show a non-Fickian part of the water uptake for all cyanate esters even at temperatures as low as 28°C. The effects of backbone structure, conversion and storage temperature are discussed in detail.

      PubDate: 2017-10-13T22:26:00Z
  • Dynamic polysulfide shape memory networks derived from elemental sulfur
           and their dual thermo-/photo-induced solid-state plasticity
    • Abstract: Publication date: Available online 12 October 2017
      Source:Reactive and Functional Polymers
      Author(s): Shuhui Zhang, Lili Pan, Lieyin Xia, Yanbin Sun, Xikui Liu
      In this study, we demonstrate the synthesis of dynamic polysulfide networks through the solution polycondensation of pentaerythritol tetra(3-mercaptopropionate) (PTMP) with elemental sulfur by a reverse vulcanization process. Elemental sulfur content as high as 51% can be incorporated into the dynamic polysulfide networks. An important feature of the resulted polysulfide networks is their catalytic-free malleability, which implies that they have both thermo- and photo-induced solid-state plasticities to obtain a complex permanent shape due to the exchange of dynamic SS bonds. These dynamic polysulfide networks have great potentials in fabricating complex three-dimensional shape memory devices for biological and mechanical applications.
      Graphical abstract image

      PubDate: 2017-10-13T22:26:00Z
  • Multiscale-structuring of rapid response shape memory polymers based on
           self-assembly reverse micelles
    • Abstract: Publication date: Available online 12 October 2017
      Source:Reactive and Functional Polymers
      Author(s): Xingjian Li, Yi Pan, Jinni Deng, Zhaohui Zheng, Xiaobin Ding
      How to reasonably fabricate shape memory polymers (SMPs) with rapid response without sacrificing the shape fixity and recovery are a critical issue but remains a challenge. Inspired by the relation between biological structure and function, a multiscale design of SMPs is reported by constructing a two-phase architecture via embedding self-assembly “reverse micelles” as elastic region into stiff matrix to enhance the elastic recovery. As a result of the two-phase architecture, the single polymer network exhibits a combination of perfect shape fixity and recovery, rapid and strong response and outstanding cycle life. The mechanism on quick response of the material is analyzed and confirmed by the study about the stress relaxation and recovery stress. Such a shape memory material may be an ideal candidate for potential applications as actuator and biomedical devices.

      PubDate: 2017-10-13T22:26:00Z
  • Dependence of color change of vinylethylene carbonate copolymers having
           N-substituted maleimides on chemical structure by acid-base switching in
           solution and solid state
    • Authors: Yoshiaki Yoshida; Takeshi Endo
      Abstract: Publication date: Available online 3 October 2017
      Source:Reactive and Functional Polymers
      Author(s): Yoshiaki Yoshida, Takeshi Endo
      The copolymers of vinylethylene carbonate (VEC) and N-substituted maleimide (NMI) having various N-substituents were synthesized by radical polymerization. The color of P(VEC/NMI)s changed from colorless to red reversibly based on the acid-base switching in solution and solid state. Furthermore, the color depth of P(VEC/NMI) solution and powder changed systematically depending on the electric effect of N-substituents. However, the copolymers of styrene and NMIs barely changed under the same conditions. These color change and depth behaviors of NMI copolymers were analyzed in detail by UV–vis and IR spectra, and the results were also supported by the density functional theory (DFT) calculation for the model compound of maleimide tautomers. Additionally, the powder color of P(VEC/NMI)s changed reversibly before and after exposure to cigarette smoke and vinegar.
      Graphical abstract image

      PubDate: 2017-10-04T21:29:55Z
      DOI: 10.1016/j.reactfunctpolym.2017.10.001
  • pH-, redox dual-sensitive poly(β-amino ester)-g-TPGS copolymer
           nanoparticles for drug delivery and inhibition of multidrug resistance in
    • Authors: Yuling Bao; Miao Kong; Xueqin Gao; Mingxing Yin; Huan Deng; Qi Tan; Qiong Wang; Songwei Tan
      Abstract: Publication date: Available online 28 September 2017
      Source:Reactive and Functional Polymers
      Author(s): Yuling Bao, Miao Kong, Xueqin Gao, Mingxing Yin, Huan Deng, Qi Tan, Qiong Wang, Songwei Tan
      To overcome multidrug resistance (MDR) in P-glycoprotein (P-gp) overexpressed cancer cells, poly(β-amino ester)-g-D-α-tocopheryl polyethylene glycol 1000 (C32-g-TPGS) copolymers were synthesized by Michael-type step polymerization. These copolymers could self-assemble into nanoparticles (NPs) and encapsulate paclitaxel (PTX) effectively. Due to the tertiary amine groups and disulfide linkages in the copolymers, the NPs exhibited a pH-, redox dual-sensitive structure change as well as the drug release behavior. The NPs were stable under normal physiological environment while they dissociated in a weakly acidic (pH5.5) or reductive (10mM DTT) environment and release the incorporated PTX quickly. Although the cell cytotoxicity of the PTX-loaded C32-g-TPGS NPs had no advantage over Taxol against drug-sensitive human ovarian A2780 cells, they did show improved cytotoxicity in drug-resistant A2780/T cells and the IC50 decreased 2 to 4-fold compared to that of Taxol, which presented a feasible way to enhance the therapeutic effect of antitumor drugs in MDR tumors.

      PubDate: 2017-10-04T21:29:55Z
      DOI: 10.1016/j.reactfunctpolym.2017.09.013
  • Preparation and properties of acetylene-terminated benzoxazine/epoxy
    • Authors: Caizhao Liu; Mingming Sun; Bin Zhang; Xugang Zhang; Jianhui Li; Lei Wang; Gang Xue; Ming Zhao; Caiyu Song; Qili Li
      Abstract: Publication date: Available online 23 September 2017
      Source:Reactive and Functional Polymers
      Author(s): Caizhao Liu, Mingming Sun, Bin Zhang, Xugang Zhang, Jianhui Li, Lei Wang, Gang Xue, Ming Zhao, Caiyu Song, Qili Li
      Acetylene-terminated benzoxazines (A-BOZs) were copolymerized with bisphenol A diglycidyl ether (DGEBA) epoxy resin to improve their processibility and adhesive properties without sacrificing much thermal performance. The three possible polymerization reactions for A-BOZs/DGEBA blends were monitored by differential scanning calorimetry (DSC) analysis and Fourier transform infrared (FTIR) spectroscopy. The rheological characterization showed that a much wider processing window could be obtained for A-BOZs/DGEBA because of the dilution effect of the epoxy. The lap shear strength of A-BOZs improved significantly with the incorporation of DGEBA. Furthermore, the cured blends also showed good heat and water resistance properties and high glass transition temperature (Tg).

      PubDate: 2017-09-26T19:28:56Z
      DOI: 10.1016/j.reactfunctpolym.2017.09.012
  • Synthesis of hydrophobic resorcinol–formaldehyde xerogels by
           grafting with silanes
    • Authors: Isabel D. Alonso-Buenaposada; M.A. Montes-Morán; J. Angel Menéndez; Ana Arenillas
      Abstract: Publication date: Available online 21 September 2017
      Source:Reactive and Functional Polymers
      Author(s): Isabel D. Alonso-Buenaposada, M.A. Montes-Morán, J. Angel Menéndez, Ana Arenillas
      Hydrophilic organic xerogels were transformed into hydrophobic materials by treating them with hexamethyldisilazane. This transformation was performed by a simple one-pot process without modifying the previously designed porosity of the xerogel, at very soft operating conditions (80°C and atmospheric pressure) in the absence of catalyst or any other additional compound. Hexamethyldisilazane reacts with dangling hydroxyl surface groups, blocks the oxygen with methylsilane groups, and prevents the formation of hydrogen bonds with water molecules. The reaction proposed was corroborated chemically by X-ray photoelectron spectroscopy and thermogravimetric analysis coupled with a mass spectrometer. The porous structure of the organic xerogel determines the minimum time for the surface modification due to steric hindrance. Therefore, the former hydrophilic surface of the organic xerogel may be transformed into a hydrophobic one by a simple process, thus leading to the possibility of designing not only the porous structure but also the surface chemistry of the resorcinol–formaldehyde xerogels to fit the requirements of an application.

      PubDate: 2017-09-26T19:28:56Z
      DOI: 10.1016/j.reactfunctpolym.2017.09.010
  • Comparison of different cyclic organic carbonates in the oxyalkylation of
           various types of lignin
    • Authors: Isabell Kühnel; Bodo Saake; Ralph Lehnen
      Abstract: Publication date: Available online 20 September 2017
      Source:Reactive and Functional Polymers
      Author(s): Isabell Kühnel, Bodo Saake, Ralph Lehnen
      The synthetic versatility and the low toxicity of cyclic alkyl carbonates has driven a wider interest in their use to access new biobased and environmentally friendly polymer building blocks, especially as alkylating reagents. Here, we report for the first time, the synthesis of biobased polyols from lignins of different sources (hardwood, softwood, annual plants) and pulping processes (organosolv, kraft, soda) by oxyalkylation with ethylene (EC), propylene (PC), butylene (BC) and glycerol carbonate (GC). The synthesis of lignin polyols was performed using optimized conditions regarding catalysts, catalyst-to-biomass ratio, reaction time, temperature and amount of cyclic carbonates. To better understand the oxyalkylation of the various types of lignins using different cyclic organic carbonates, the generated polyols were comprehensively characterized by FTIR, 1H, 13C, and 31P NMR spectroscopy as well as size exclusion chromatography (SEC). Emphasis was set on the hydroxyl amount, the degree of substitution (DS) and the alkyl chain. This oxyalkylation strongly facilitates the generation of a uniform lignin polyol equipped with two alkyl units on the aliphatic and phenolic hydroxyl groups. Higher degrees of substitution were achieved using cyclic organic carbonates in the following order EC>GC>PC>BC, reaching a maximum of DS 0.96 for a hardwood kraft lignin. Additionally, the influence of ash, sulfur and polysaccharide impurities as well as lignins molar masses was elucidated.
      Graphical abstract image

      PubDate: 2017-09-26T19:28:56Z
      DOI: 10.1016/j.reactfunctpolym.2017.09.011
  • Editors and Editorial Board
    • Abstract: Publication date: October 2017
      Source:Reactive and Functional Polymers, Volume 119

      PubDate: 2017-09-20T19:08:51Z
  • Mixed polycarbonate prodrug nanoparticles with reduction/pH
           dual-responsive and charge conversional properties
    • Authors: Lin Yu; Songwei Tan; Zhao Li; Zhen Zheng; Linzhu Zhou; Yue Su; Xinling Wang
      Abstract: Publication date: Available online 19 September 2017
      Source:Reactive and Functional Polymers
      Author(s): Lin Yu, Songwei Tan, Zhao Li, Zhen Zheng, Linzhu Zhou, Yue Su, Xinling Wang
      To build a multifunctional and biodegradable drug delivery system, positively and negatively charged functional polycarbonates (PCs) were synthesized and then assembled into nanoparticles (NPs) in pH7.4 PBS via electrostatic and hydrophobic interaction. Hydrazone linked doxorubicin (DOX) and disulfide functional groups were conjugated to the propargyl-functional PC to achieve the positive PC, PC(Arss-N(CH3)2-DOX). In pH7.4 PBS, the positive PCs could form charged NPs with reduction/pH dual sensitive behaviors. The negative PCs, poly(ethylene glycol)-block-1,2-dicarboxylic-cyclohexene anhydride modified amino polycarbonate (PEG-PCDCA) and PCDCA, were used to modulate the size/size distribution of the prodrug NPs and strengthen the blood circulation ability of the NPs. The surface nature of NPs could change from negative in physical pH to positive at tumor extracellular pH (pHe). In vitro study showed that the NPs could exhibit effective cellular uptake, intracellular drug release, and obvious cytotoxicity against Hela tumor cells. All these indicated that the NPs would be a potential for the anti-tumor drug delivery system.

      PubDate: 2017-09-20T19:08:51Z
      DOI: 10.1016/j.reactfunctpolym.2017.09.009
  • Preparation and characterization of cardamom extract-loaded gelatin
           nanoparticles as effective targeted drug delivery system to treat
    • Authors: H. Nejat; M. Rabiee; R. Varshochian; M. Tahriri; H.E. Jazayeri; J. Rajadas; H. Ye; Z. Cui; L. Tayebi
      Abstract: Publication date: Available online 18 September 2017
      Source:Reactive and Functional Polymers
      Author(s): H. Nejat, M. Rabiee, R. Varshochian, M. Tahriri, H.E. Jazayeri, J. Rajadas, H. Ye, Z. Cui, L. Tayebi
      The purpose of this research study was to prepare and characterize cardamom extract-loaded gelatin nanoparticles (CE-loaded GNPs) with a diameter≤200nm as a potent drug delivery system (DDS) for treatment of glioblastoma, which is the most common and aggressive type of brain tumor. The BBB poses physical and biological limitations to drug diffusion to reach target tissues. Polymeric nanoparticles, like gelatin, are suitable vehicles for drug delivery into the central nervous system (CNS). They are able to cross the BBB. Hence, we prepared CE-loaded GNPs by a two-step desolvation method. Seizures are detrimental secondary effects of brain tumors. Therefore, we used cardamom extract, which is an herbal anticancer and antiepileptic drug without any side effects, instead of synthetic drugs to load in gelatin nanoparticles during the particles preparation. We also prepared gelatin Type A and Type B nanoparticles for size comparison. Encapsulation efficiency, mean particle size, zeta potential and in vitro release profile were performed, and particle size analysis, dynamic light scattering (DLS), UV–Vis spectrophotometry, differential scanning calorimetry (DSC), X-Ray diffraction (XRD), scanning electron microscopy (SEM) and field emission scanning electron microscopy (FE-SEM) were employed to evaluate structural and physicochemical properties of the samples. CE-loaded GNPs were obtained with diameters of 40–200nm, zeta potential of −40.1mV and entrapment efficiency (EE) of 70%. The ratio of extract to polymer, 1:20, was revealed to be more suitable in obtaining smaller nanoparticles without any precipitate or aggregation. We also examined cytotoxic effects of CE and CE-loaded GNPs on human glioblastoma cancer U87MG cells.

      PubDate: 2017-09-20T19:08:51Z
      DOI: 10.1016/j.reactfunctpolym.2017.09.008
  • Quaternized poly (poly(ethylene glycol)methyl ether methacrylate)-b-poly
           (2-(dimethylamino)ethyl methacrylate) as block copolymers by sequential
           monomer addition: Dispersion of copper phthalocyanine
    • Authors: Byoungjae Kim; Jonghwa Jeong; Aruna Kumar Mohanty; Taeheon Lee; Sangmin Han; Jiwon Heo; Ki-Suck Jung; Jin-goo Kim; Hyun-jong Paik
      Abstract: Publication date: Available online 18 September 2017
      Source:Reactive and Functional Polymers
      Author(s): Byoungjae Kim, Jonghwa Jeong, Aruna Kumar Mohanty, Taeheon Lee, Sangmin Han, Jiwon Heo, Ki-Suck Jung, Jin-goo Kim, Hyun-jong Paik
      We synthesized poly (poly(ethylene glycol)methyl ether methacrylate)-b-poly (2-(dimethylamino)ethyl methacrylate) (p(PEGMA-b-DMAEMA)) by sequential addition of monomers and its quaternized products (p(PEGMA-b-(DMAEMA-co-QDMAEMA)) from the reaction with benzyl chloride for dispersion of copper phthalocyanine (CuPc). The structure of block copolymers was characterized by 1H NMR and SEC analysis. The block copolymers were investigated for their dispersion performance of CuPc in propylene glycol monomethyl ether acetate. The dispersion states of CuPc by dispersants were studied using dynamic light scattering (DLS).

      PubDate: 2017-09-20T19:08:51Z
      DOI: 10.1016/j.reactfunctpolym.2017.09.007
  • Mechanically robust, photopatternable conductive hydrogel composites
    • Authors: Ramendra K. Pal; Emigdio E. Turner; Benjamin H. Chalfant; Vamsi K. Yadavalli
      Abstract: Publication date: Available online 18 September 2017
      Source:Reactive and Functional Polymers
      Author(s): Ramendra K. Pal, Emigdio E. Turner, Benjamin H. Chalfant, Vamsi K. Yadavalli
      Electrically conductive hydrogels (ECH) which are composites of hydrogels and conducting polymers, exhibit a powerful combination of biocompatibility and conductivity. They combine the high hydration and soft mechanical nature of hydrogel networks, with the electrochemical functionality of conducting components allowing precise control of properties. Interest in these materials has increased recently for applications in tissue engineering, biosensing, and flexible and implantable bioelectronics. Here, we demonstrate a dispersion of poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) in a photocurable poly(ethylene glycol)-diacrylate (PEG-DA) matrix to form functional hydrogels via a facile, fully aqueous, photopolymerization process. We report on effect of various compositions of the conducting polymer, tuning of mechanical and electrochemical properties, and the ability to micropattern the composite using photolithography. The electrical properties of the ECH are characterized by cyclic voltammetry, four-point probe, and conductive atomic force microscopy to reveal the competitive properties of the composite, with minimal leaching and stability over time. We further show how minute amounts of graphene dopant can be used to engineer mechanical and electrochemical properties. Overall, the graphene-hydrogel-conducting polymer composite structure enables optimization of various properties by synergistically integrating the electrochemical and mechanical properties of graphene and the PEDOT:PSS, with the biocompatibility and micropatterning of the soft hydrogel matrix.

      PubDate: 2017-09-20T19:08:51Z
      DOI: 10.1016/j.reactfunctpolym.2017.09.006
  • Preparation and characterization of pH-responsive poly(N,N-dimethyl
           acrylamide-co-methacryloyl sulfadimethoxine) hydrogels for application as
           food freshness indicators
    • Authors: Seunghye Baek; Dowan Kim; Sung Lan Jeon; Jongchul Seo
      Abstract: Publication date: Available online 17 September 2017
      Source:Reactive and Functional Polymers
      Author(s): Seunghye Baek, Dowan Kim, Sung Lan Jeon, Jongchul Seo
      A series of poly(N,N-dimethyl acrylamide-co-methacryloyl sulfadimethoxine) (poly(DMA-co-SDM)) hydrogels with different ratios of N,N-dimethylacrylamide (DMA) and methacryloyl sulfadimethoxine monomer (SDM) were synthesized by free radical polymerization. The pKa values of the monomer and hydrogels were measured to investigate the extent to which their pH-responsive properties were affected by the ionizable sulfonamide groups. Further, buffer solutions of pH2.0–10.0, considered as the spoilage metabolites, were used to confirm the change in the pH-responsive properties. The composition ratios of DMA and SDM strongly affected the pKa values of the hydrogels, contributing to differences in the ionization around their pKa values. As a result, all the hydrogels showed different changes in their appearance, from opaque to transparent or vice versa at certain pH values. The change in the transparency of the as-prepared hydrogels is strongly dependent on both the change in the pH and the amount of buffer solution, which mainly occurs owing to the change in the quality of a product with time. Therefore, the synthesized pH-responsive poly(DMA-co-SDM) hydrogels can be potentially applied as transparency changing indicators in response to metabolites released owing to the change in the quality of the food products.

      PubDate: 2017-09-20T19:08:51Z
      DOI: 10.1016/j.reactfunctpolym.2017.09.003
  • Molybdenum and tungsten disulfides surface-modified with a conducting
           polymer, polyaniline, for application in electrorheology
    • Authors: Jaroslav Stejskal; Miroslav Mrlík; Tomáš Plachý; Miroslava Trchová; Jana Kovářová; Yu Li
      Abstract: Publication date: Available online 17 September 2017
      Source:Reactive and Functional Polymers
      Author(s): Jaroslav Stejskal, Miroslav Mrlík, Tomáš Plachý, Miroslava Trchová, Jana Kovářová, Yu Li
      Molybdenum and tungsten sulfides are semiconducting materials with flake-like morphology. Their applicability in electrorheological suspensions was enabled by the coating with a conducting polymer, polyaniline, after its conversion to non-conducting polyaniline base. For instance, the conductivity of tungsten sulfide, 0.056Scm−1, increased to 0.98Scm−1 after coating with polyaniline, and was conveniently reduced to 6.3×10−6 Scm−1 after conversion to polyaniline base. Such approach reduces the potential current drifts in electrorheological suspensions and allows for the application of sulfides in electrorheology. The optical microscopy demonstrated the formation of particles chains in silicone-oil suspensions after application of electric field strength. The electrorheological performance was assessed by the measurement of viscosity on the shear rate in the absence and in the presence of electric field and it is discussed on the bases dielectric spectra.

      PubDate: 2017-09-20T19:08:51Z
      DOI: 10.1016/j.reactfunctpolym.2017.09.004
  • Nanostructuration of polysilane-SiQDs composite by pulsed electrical
           discharges in water
    • Authors: Liviu Sacarescu; Mihaela Simionescu; Gabriela Sacarescu; Antje Quade; Juergen F. Kolb; Camelia Miron
      Abstract: Publication date: Available online 15 September 2017
      Source:Reactive and Functional Polymers
      Author(s): Liviu Sacarescu, Mihaela Simionescu, Gabriela Sacarescu, Antje Quade, Juergen F. Kolb, Camelia Miron

      PubDate: 2017-09-20T19:08:51Z
      DOI: 10.1016/j.reactfunctpolym.2017.09.005
  • Synthesis of polyfluorene and oligofluorene with N1-hexylcytosine side
           chains and their sensing ability for nucleosides
    • Authors: Isao Yamaguchi; Koji Miyawaki
      Abstract: Publication date: Available online 9 September 2017
      Source:Reactive and Functional Polymers
      Author(s): Isao Yamaguchi, Koji Miyawaki
      Polyfluorene (PF) and oligofluorene (OF) with N 1-hexylcytosine side chains were synthesized by Pd-complex-catalyzed condensation reactions starting from a newly synthesized monomer. The UV–vis spectra of the PF exhibit the absorption maximum at a longer wavelength than that of the OF, thus revealing that a π-conjugation system extends along the polymer chain. The PF and OF are photoluminescent in solution, and their photoluminescence (PL) intensities are gradually decreased by the addition of nucleosides such as adenosine, cytidine, and guanosine to the solution. The decrease in PL intensity is likely caused by photoinduced charge transfer (PCT) from the PF's and OF's backbones to the nucleosides, within the complexes generated by hydrogen bonding between the PF and OF cytosine group at their side chains and the nucleosides. Among the nucleosides, guanosine acted as the most effective PL quenching agent. Cyclic voltammetry (CV) analysis of the OF showed that it is electrochemically active.

      PubDate: 2017-09-14T18:46:07Z
      DOI: 10.1016/j.reactfunctpolym.2017.09.001
  • Biodegradable-stimuli sensitive xanthan gum based hydrogel: Evaluation of
           antibacterial activity and controlled agro-chemical release
    • Authors: Sukriti; B.S. Kaith; Rajeev Jindal; Manorma Kumari; Mohinder Kaur
      Abstract: Publication date: Available online 5 September 2017
      Source:Reactive and Functional Polymers
      Author(s): Sukriti, B.S. Kaith, Rajeev Jindal, Manorma Kumari, Mohinder Kaur
      Biodegradable hydrogel based on xanthan gum graft co-polymerized with polyacrylic acid was fabricated by free radical polymerization in presence of microwave radiations and its potential utility as bactericidal agent along with controlled agro-chemical release device was explored. The biodegradability was tested using soil burial method and it has been observed that the synthesized semi-interpenetrating (semi-IPN) was degraded upto 78.3% by weight with 1.11% rate of degradation per day within 70days. FT-IR and SEM micrographs further confirmed the biodegradable nature of the test sample. The Phaseolus vulgaris plants were grown in the soil containing the degraded sample and depicted healthy growth characteristic indicated the absence of any harmful end products from degraded sample. The semi-IPN was also found to bactericidal in nature against bacterial strains such as Bacillus subtilis and Salmonella enteritis probably due to ion-exchange effect. Also, the synthesized sample was used for the controlled release of urea and its release dynamics were studied. The macromolecular relaxation of the matrix was found to be comparable to diffusion rate of urea indicated by the non-Fickian (n =0.76) diffusion mechanism. Initial diffusion coefficient (Di =3.50×10−5 m2 h−1) was found to be greater than late diffusion coefficient (DL =2.31×10−6 m2 h−1) and indicated the prolonged release of urea. So, synthesized semi-IPN could be labeled as biodegradable, non-toxic, stimuli sensitive, antibacterial along with controlled release device for agro-chemicals.
      Graphical abstract image

      PubDate: 2017-09-08T18:25:18Z
      DOI: 10.1016/j.reactfunctpolym.2017.08.012
  • Editors and Editorial Board
    • Abstract: Publication date: September 2017
      Source:Reactive and Functional Polymers, Volume 118

      PubDate: 2017-09-02T16:13:50Z
  • Optimization of pH-responsive carboxymethylated iota-carrageenan/chitosan
           nanoparticles for oral insulin delivery using response surface methodology
    • Authors: Pratyusa Sahoo; Kok Hoong Leong; Shaik Nyamathulla; Yoshinori Onuki; Kozo Takayama; Lip Yong Chung
      Abstract: Publication date: Available online 1 September 2017
      Source:Reactive and Functional Polymers
      Author(s): Pratyusa Sahoo, Kok Hoong Leong, Shaik Nyamathulla, Yoshinori Onuki, Kozo Takayama, Lip Yong Chung
      In designing an oral delivery method for insulin, we previously reported that pH-responsive carboxymethylated kappa-carrageenan-based microparticles protected insulin from acid degradation during transport through the gastrointestinal tract. However, the low surface-to-volume ratio of these microparticles and the presence of only one sulfate group in each kappa-carrageenan subunit for insulin stabilization may lead to a suboptimal delivery efficiency. To improve the delivery efficiency, we designed a nanoparticle from chitosan (CS) and carboxymethylated iota-carrageenan (CMCi) that possessed two sulfate groups per subunit based on response surface methodology together with multivariate spline interpolation (RSMMSI). The resulting optimized nanoparticles had a zeta potential, mean particle size, loading capacity and entrapment efficiency of 52.5±0.5mV, 613±41nm, 10.7±0.6%, and 86.9±2.6%, respectively. The release of insulin from the optimized nanoparticles was low (4.91±0.24%) in simulated gastric fluid (SGF) and high (86.64±2.2%) in simulated intestinal fluid (SIF) during a 12-h release study, thereby showing a pH-responsive drug release property. The nanoparticles were stable at 4°C and −20°C for at least 90days and for up to 7days at room temperature. The RSMMSI technique successfully expedited the design of the nanoparticles, which could serve as an improved oral insulin drug delivery system.
      Graphical abstract image

      PubDate: 2017-09-02T16:13:50Z
      DOI: 10.1016/j.reactfunctpolym.2017.08.014
  • Preparation and gas transport properties of thermally induced rigid
           membranes of copolyimide containing cardo moieties
    • Authors: Yunhua Lu; Jican Hao; Lin Li; Jing Song; Guoyong Xiao; Hongbin Zhao; Zhizhi Hu; Tonghua Wang
      Abstract: Publication date: Available online 1 September 2017
      Source:Reactive and Functional Polymers
      Author(s): Yunhua Lu, Jican Hao, Lin Li, Jing Song, Guoyong Xiao, Hongbin Zhao, Zhizhi Hu, Tonghua Wang
      The diamine monomer with ortho-hydroxyl groups and fluorene moiety, 9,9-bis (3-amino-4-hydroxyphenyl)fluorene (BisAHPF), was prepared. The 6FDA-FDA-BisAHPF copoly(amic acid) (PAA) solution was synthesized from the diamines 9,9-bis(4-aminophenyl)fluorene (FDA), BisAHPF and aromatic dianhydride 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride (6FDA) by a low-temperature solution polymerization. The thernally treated PAA films were used as precursor to prepare thermally induced rigid membranes in N2 and air atmosphere at the temperature range of 300–480°C, respectively. The thermally induced rigid membranes included thermal oxidative membranes and thermally rearrangement (TR) membranes. Their physical and chemical properties were characterized by FTIR, XPS, XRD, DSC and TGA. Single gas permeation performances of thermally induced rigid membranes were studied for five representative gases of interest including H2, O2, N2, CO2, and CH4. Highly gas permeability were obtained after the thermal treatment. Therefore, the introduction of “cardo” moieties helped to improve the gas permeability. In addition, a proper thermal treatment could tune to the gas separation performance of the thermally induced rigid membrane materials

      PubDate: 2017-09-02T16:13:50Z
      DOI: 10.1016/j.reactfunctpolym.2017.08.013
  • Controlled delivery of oral insulin aspart using pH-responsive
           alginate/κ-carrageenan composite hydrogel beads
    • Authors: Hui-Peng Lim; Chien-Wei Ooi; Beng-Ti Tey; Eng-Seng Chan
      Abstract: Publication date: Available online 1 September 2017
      Source:Reactive and Functional Polymers
      Author(s): Hui-Peng Lim, Chien-Wei Ooi, Beng-Ti Tey, Eng-Seng Chan
      Diabetes mellitus is a global epidemic currently affecting >415 million people worldwide. It is a disease caused by either the lack of or a resistance to the insulin, which is a glucose-regulating hormone, in a patient. The low compliance with the subcutaneous administration of insulin by diabetic patients has urged the need for an oral-route delivery of insulin. There are two important criteria for an effective oral delivery of insulin, namely the protection of encapsulated insulin from the harsh acidic conditions in the stomach, and the controlled release of insulin at the targeted site of absorption (i.e., the intestine). In this work, the pH-responsive composite hydrogel beads made of the naturally-derived biopolymers (i.e., alginate and κ-carrageenan) were formed using the extrusion-dripping method. The composite hydrogel beads were tested as the delivery vehicles for insulin aspart. At pH1.2, the composite hydrogel beads successfully retained the insulin aspart through electrostatic interaction between the positively charged insulin aspart and the negatively charged sulfate groups of the κ-carrageenan polymers. At pH7.4, insulin aspart was released in a gradual manner, and the release profile approached zero-order kinetic when the concentration of κ-carrageenan used in the formation of hydrogel bead increased. After incubation of composite hydrogel beads in acidic simulated gastric medium, there was approximately 65% of the insulin aspart remained biologically active in the beads. The results suggest that the alginate/κ-carrageenan composite hydrogel bead is a promising delivery system for the oral insulin aspart.

      PubDate: 2017-09-02T16:13:50Z
      DOI: 10.1016/j.reactfunctpolym.2017.08.015
  • Molecular integration on phospholipid polymer-coated magnetic beads for
           gene expression analysis in cells
    • Authors: Kazuhiko Ishihara; Yoshito Fukuda; Tomohiro Konno; Yuuki Inoue
      Abstract: Publication date: Available online 31 August 2017
      Source:Reactive and Functional Polymers
      Author(s): Kazuhiko Ishihara, Yoshito Fukuda, Tomohiro Konno, Yuuki Inoue
      Magnetic polymer beads, composed of a polystyrene core and hydrophilic poly(2-methacryloyloxyethyl phosphorylcholine (MPC)) graft layer, containing magnetic nanoparticles were prepared for analyzing genes in the cells. The initiator group for atom transfer radical polymerization (ATRP) was provided on the surface of the beads and polymerization of MPC created the poly(MPC) graft layer. The terminal bromine group of poly(MPC) chains converted to a reactive group. Streptavidin was immobilized using the terminal reactive group in the poly(MPC) chains for capturing the biotinated DNA primer of the polymerase chain reaction (PCR). After selective binding of three kinds of messenger RNA from the cell lysate, PCR was carried out to increase complementary DNA. The polymer beads were stable even under the PCR thermal cycling conditions, and dispersed again easily. The magnetic polymer beads can be candidate solid support for PCR of cell lysates.

      PubDate: 2017-09-02T16:13:50Z
      DOI: 10.1016/j.reactfunctpolym.2017.08.011
  • Thermoresponsive hydrogels with covalently incorporated trehalose as
           protein carriers
    • Authors: Małgorzata Burek; Sylwia Waśkiewicz; Stefan Awietjan; Ilona Wandzik
      Abstract: Publication date: Available online 25 August 2017
      Source:Reactive and Functional Polymers
      Author(s): Małgorzata Burek, Sylwia Waśkiewicz, Stefan Awietjan, Ilona Wandzik
      A series of thermoresponsive hydrogels containing covalently incorporated trehalose, the well-known protein stabilizing disaccharide, was synthesized with the aim to obtain bioprotective carriers for protein release. Smart materials with trehalose present only in cross-links or both in cross-links and as pending moieties, were fabricated by redox-initiated radical copolymerization, with N-isopropylacrylamide used as the main monomer. In order to modify thermoresponsive properties, hydrogels containing more hydrophilic comonomers, acrylamide or N-(2-hydroxyethyl)acrylamide, were also obtained. The susceptibility of the cross-linker to undergo acid-catalyzed hydrolysis was used to disintegrate the polymer network and estimate the composition of the synthesized materials. The properties of hydrogels, which include: swelling capacity, thermoresponsive behavior, rheological characteristic, internal microstructure and the rate of acid-catalyzed degradation, were found to be dependent on both trehalose as well as hydrophilic comonomers. BSA and β-Galactosidase were chosen as model proteins for the release study from obtained hydrogels. The release profiles were shown to vary significantly depending on hydrogel form, the polymer network composition and temperature.

      PubDate: 2017-09-02T16:13:50Z
      DOI: 10.1016/j.reactfunctpolym.2017.08.009
  • PCL-b-P(MMA-co-DMAEMA)2 new triblock copolymer for novel pH-sensitive
           nanocapsules intended for drug delivery to tumors
    • Authors: Camila Franco; Michelli Barcelos Antonow; Aline Beckenkamp; Andréia Buffon; Taíse Ceolin; Marli Luiza Tebaldi; Gustavo Pozza Silveira; Silvia Stanisçuaski Guterres; Adriana Raffin Pohlmann
      Abstract: Publication date: Available online 24 August 2017
      Source:Reactive and Functional Polymers
      Author(s): Camila Franco, Michelli Barcelos Antonow, Aline Beckenkamp, Andréia Buffon, Taíse Ceolin, Marli Luiza Tebaldi, Gustavo Pozza Silveira, Silvia Stanisçuaski Guterres, Adriana Raffin Pohlmann
      A novel poly(ε-caprolactone) (PCL) and poly [(methyl methacrylate)-co-(2-dimethylamino)ethyl methacrylate)2] block copolymer, PCL-b-P(MMA-co-DMAEMA)2, was synthesized using atom transfer radical polymerization to obtain pH-sensitive nanocapsules intended for drug delivery to solid tumors. The synthesis was performed using PCL:DMAEMA:MMA at two different molar proportions 0.2:10:1 and 0.7:33:1. Nanocapsules prepared using PCL-b-P(MMA-co-DMAEMA)2 proved sensitivity to pH, presenting z-average hydrodynamic diameters of 73 and 71nm at pH7.4, and 96 and 101nm at pH5.5, respectively, because of the decrease in the diffusion coefficient of the nanocapsules due to the increase in amine protonation forming ammonium at the surface. Zeta potential at pH7.2 was +23mV for batch 1 and +13mV for batch 2. In vitro cytotoxicity of the materials (solutions) and the nanocapsules (dispersed in water) was evaluated in a tumoral cell model (human breast adenocarcinoma cell line, MCF-7) using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay (MTT). The homopolymers PDMAEMA and PMMA showed low cytotoxicity up to 0.60 and 0.44mmolL−1, respectively. After applying the nanoformulation, the cell viability was not affected for copolymer concentrations up to 340mgL−1. The results showed the new triblock copolymer is a promising material to be used in novel nanocapsule formulations intended for drug delivery to solid tumors.

      PubDate: 2017-09-02T16:13:50Z
      DOI: 10.1016/j.reactfunctpolym.2017.08.010
  • Development of vinyl ester resins with improved flame retardant properties
           for structural marine applications
    • Authors: Baljinder K. Kandola; John R. Ebdon; Chen Zhou
      Abstract: Publication date: Available online 10 August 2017
      Source:Reactive and Functional Polymers
      Author(s): Baljinder K. Kandola, John R. Ebdon, Chen Zhou
      This work builds on our previous experience of blending and co-curing an unsaturated polyester resin with other relatively inexpensive, but more flame retardant resins such as chemically modified phenolic resins, and extends this technology to the almost equally flammable vinyl ester resins, commonly used in marine composites. It has been demonstrated that two commercial vinyl ester resins (Scott-Bader, UK), one epoxy based (Crystic VE 676) and the other novolac based (Crystic VE 673), may be blended with two different commercial low molecular weight phenolic resoles (Sumitomo Bakelite Europe NV), one unmodified (Durez 33156) and the other containing allyl groups (Methylon 75108) and the blends cured (crosslinked) to give blended resins with good flame retardance, in several respects better than that of the unblended vinyl ester resins. Compatibility of the vinyl esters with the Methylon resole is however better than with the Durez, which tends to give phase-separated blends, and thus blends having poor physical and mechanical properties. Moreover, the compatibility of the novolac-based VE with both Durez and Methylon is worse than blends of the unsaturated polyester with Methylon and Durez. This compatibility issue and derived flammability properties of different blends are discussed in terms of their chemical structures.

      PubDate: 2017-09-02T16:13:50Z
      DOI: 10.1016/j.reactfunctpolym.2017.08.006
  • Prediction of the char formation of polybenzoxazines: The effect of
           heterogeneities in the crosslinked network to the prediction accuracy in
           quantitative structure-properties relationship (QSPR) model
    • Authors: M. Sairi; B.J. Howlin; D.J. Watson; I. Hamerton
      Abstract: Publication date: Available online 8 August 2017
      Source:Reactive and Functional Polymers
      Author(s): M. Sairi, B.J. Howlin, D.J. Watson, I. Hamerton
      Molecular Operating Environment (MOE) software has great potential when combined with the qualitative structure-property relationship (QSPR) approach, and was proven to be useful to make good prediction models for series of polybenzoxazines [1–3]. However, the effect of heterogeneities in the crosslinked network to the prediction accuracy is yet to be tested. It was found that polybenzoxazines with polymerisable functional group (e.g. acetylene-based benzoxazines) form up to 40% higher char yield compared to their analogue polybenzoxazines due to the contribution of the polymerisable functional group (e.g. ethynyl triple bond) in the cross-linked network. In order to investigate the effect of the inconsistent cross-linking network, a data set consisting of thirty-three benzoxazines containing various structures of benzoxazines was subdivided into two smaller data sets based on their functional group, either benzoxazines with polymerisable functional group (acetylene-based benzoxazines set (Ace-M)) or non-polymerisable functional group (aniline-based benzoxazines (Ani-M)). Char yield predictions for the polybenzoxazines for these data sets (Ace-M and Ani-M) were compared with the larger thirty-three polybenzoxazines data set (GM) to investigate the effect of the inconsistency in crosslink network on the quality of prediction afforded by the model. Prediction performed by Ace-M and Ani-M were found to be more accurate when compared with the GM with total prediction error of 3.15% from both models compared to the GM (4.81%). Ace-M and Ani-M are each better at predicting the char yields of similar polybenzoxazines (i.e. one model is specific for a polymerisable functional group; the other for non-polymerisable functional group), but GM is more practical as it has greater ‘general’ utility and is applicable to numerous structures. The error shown by GM is considerably small and therefore it is still a good option for prediction and should not be underestimated.

      PubDate: 2017-09-02T16:13:50Z
      DOI: 10.1016/j.reactfunctpolym.2017.08.002
  • Glutathione and endosomal pH-responsive hybrid vesicles fabricated by
           zwitterionic polymer block poly(l-aspartic acid) as a smart anticancer
           delivery platform
    • Authors: Renjith P. Johnson; Saji Uthaman; Rimesh Augustine; Yu Zhang; Hwa Jin; Chang In Choi; In-Kyu Park; Il Kim
      Abstract: Publication date: Available online 1 August 2017
      Source:Reactive and Functional Polymers
      Author(s): Renjith P. Johnson, Saji Uthaman, Rimesh Augustine, Yu Zhang, Hwa Jin, Chang In Choi, In-Kyu Park, Il Kim
      Zwitterionic hybrid block copolymer based nanocarriers are ideal candidates for drug delivery applications due the higher resistance to nonspecific protein adsorption in complex media compared to nonionic polymers. Especially, zwitterionic poly(2-methacryloyloxyethyl phosphorylcholine) p(MPC) based nanocarriers can maintain its stability during circulation in complex media, such as serum. Thus, a series of bioreducible and pH-responsive zwitterionic/amphiphilic block copolymers, poly(2-methacryloyloxyethyl phosphorylcholine)50-block-poly(l-aspartic acid)n (p(MPC)50–b–p(AA)n) (n =10, 25, 50, 75), bearing a degradable disulfide linker have been synthesized and exploited as dual-stimuli-responsive drug delivery vehicle of the chemotherapeutic drug, doxorubicin (Dox). Dox was successfully loaded into uniform vesicles (∼100nm) fabricated from p(MPC)50–b–p(AA)n and the release performance was investigated under different pH conditions and with a range of concentrations of the reducing agent, 1,4-dithiothreitol (DTT). At physiological conditions, increasing concentrations of DTT resulted in faster Dox release from vesicles. Dox release at elevated DTT concentrations was more effective at pH5.5 than at pH7.5. Blank vesicles were non-toxic over a wide concentration range when tested in normal cell lines (0.01–100μg/mL). Vesicles efficiently encapsulated Dox and the dual stimuli-responsive disassembly results demonstrated controlled and sustained release of Dox tin 4T1 cancer cells to confer dose-dependent cytotoxicity. Thus, the bioreducible and pH sensitive vesicles appear to be a promising theranostic platform for drug delivery applications.
      Graphical abstract image

      PubDate: 2017-08-03T16:40:31Z
      DOI: 10.1016/j.reactfunctpolym.2017.07.010
  • Chitosan–silica anion exchange membrane for the vanadium redox flow
           energy storage battery applications
    • Authors: Shu-Ling Huang; Mei-Ling Chen; Yung-Sheng Lin
      Abstract: Publication date: Available online 31 July 2017
      Source:Reactive and Functional Polymers
      Author(s): Shu-Ling Huang, Mei-Ling Chen, Yung-Sheng Lin
      In this study, chitosan–silica anion exchange membranes were synthesized using a sol-gel process and nucleophilic substitution reaction. The basic properties of the synthesized ion exchange membranes were assessed, including water uptake, contact angle, ion exchange capacity, vanadium ion permeability, impedance, and conductivity. Furthermore, we used the chitosan–silica membranes as a separator in a single all‑vanadium redox flow battery system to investigate their charge–discharge characteristics. We then compared the performance of the chitosan–silica membranes with that of commercially available membranes in terms of impedance as a function of thickness and efficiency. In addition, we studied the relationships between the basic properties and the charge–discharge efficiency of the membranes by varying the concentration of (3-glycidyloxypropyl)trimethoxysilane (GPTMS). The results demonstrate that the mechanical strength and chemical stability of the synthesized chitosan–silica membranes were enhanced with the increase in GPTMS concentration. The chitosan–silica anion exchange membranes exhibited lower vanadium ion permeability and higher coulombic efficiency, and have a lower cost than their commercial counterparts. The highest measured coulombic efficiency reached 91%.

      PubDate: 2017-08-03T16:40:31Z
      DOI: 10.1016/j.reactfunctpolym.2017.07.011
  • Cast polyurethanes obtained from reactive recovered polyol intermediates
           via crude glycerine decomposition process
    • Authors: Patrycja Jutrzenka Trzebiatowska; Ilona Deuter; Janusz Datta
      Abstract: Publication date: Available online 31 July 2017
      Source:Reactive and Functional Polymers
      Author(s): Patrycja Jutrzenka Trzebiatowska, Ilona Deuter, Janusz Datta
      In this work, the possibility of applying intermediates from polyurethane waste recycling in polyurethane synthesis was presented. Polyurethanes were synthesised in a two-step method using a mixture of petrochemical polyol and glycerolysate as a reactive component and 4,4-diphenylmethane diisocyanate (MDI). Glycerolysates were produced during decomposition of polyurethane elastomer by crude glycerine from biodiesel production. The glycerolysates were incorporated into polyurethane structure and co-created a soft segment with their functional groups. Chemical structure and properties of the cast polyurethanes were characterised by Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), dynamic mechanical analysis (DMA) and mechanical tests. Results showed that higher incorporation of glycerolysates shifts the glass transition to higher temperatures and the mechanical properties indicates that material exhibits more stiff structure. Prepared polyurethanes which contained glycerolysates have good and similar (in a small amount of glycerolysate) properties to the reference polyurethane which indicates the possibility of glycerolysate application as a polyol in the polyurethane synthesis.

      PubDate: 2017-08-03T16:40:31Z
      DOI: 10.1016/j.reactfunctpolym.2017.07.009
  • Functional polylactide by cationic ring-opening copolymerization of
           lactide with epoxides
    • Authors: Melania Bednarek; Malgorzata Basko; Przemysław Kubisa
      Abstract: Publication date: Available online 29 July 2017
      Source:Reactive and Functional Polymers
      Author(s): Melania Bednarek, Malgorzata Basko, Przemysław Kubisa
      Sequential and simultaneous cationic copolymerizations of lactide with commercial functional epoxides, allyl glycidyl ether, glycidyl propargyl ether, and epichlorohydrin, catalyzed by a protic acid in a one-pot process were studied. Block and gradient polylactide-based medium-molecular-weight copolymers with several alkene, alkyne, or chloromethyl groups at one chain end or with gradient distribution along the polymer chain were successfully synthesized, as proven by 1H NMR, SEC, and MALDI TOF analyses. Functional polylactides were further subjected to thiol-yne addition, cycloaddition of azide, or reaction with tertiary amine, respectively, to demonstrate the reactivity of the introduced functional groups.

      PubDate: 2017-08-03T16:40:31Z
      DOI: 10.1016/j.reactfunctpolym.2017.07.008
  • Tuning properties of poly(ethylene glycol)-block-poly(simvastatin)
           copolymers synthesized via triazabicyclodecene
    • Authors: Theodora A. Asafo-Adjei; Thomas D. Dziubla; David A. Puleo
      Abstract: Publication date: Available online 27 July 2017
      Source:Reactive and Functional Polymers
      Author(s): Theodora A. Asafo-Adjei, Thomas D. Dziubla, David A. Puleo
      Simvastatin was polymerized into copolymers to better control drug loading and release for therapeutic delivery. When using the conventional stannous octoate catalyst in ring-opening polymerization (ROP), reaction temperatures ≥200°C were required, which promoted uncontrollable and undesirable side reactions. Triazabicyclodecene (TBD), a highly reactive guanidine base organocatalyst, was used as an alternative to polymerize simvastatin. Polymerization was achieved at 150°C using 5kDa methyl-terminated poly(ethylene glycol) (mPEG) as the initiator. ROP reactions with 2kDa or 550Da mPEG initiators were also successful using TBD at 150°C instead of stannous octoate, which required a higher reaction temperature. Biodegradability of the poly(simvastatin) copolymer in phosphate-buffered saline was also improved, losing twice as much mass than the copolymer synthesized via stannous octoate. The three copolymers exhibited modified rates of simvastatin release, demonstrating tunability for drug delivery applications.

      PubDate: 2017-08-03T16:40:31Z
      DOI: 10.1016/j.reactfunctpolym.2017.07.004
  • Slide-ring shape memory polymers with movable cross-links
    • Authors: Xingjian Li; Yaru Wang; Ruiqing Wu; Yi Pan; Zhaohui Zheng; Xiaobin Ding
      Abstract: Publication date: Available online 25 July 2017
      Source:Reactive and Functional Polymers
      Author(s): Xingjian Li, Yaru Wang, Ruiqing Wu, Yi Pan, Zhaohui Zheng, Xiaobin Ding
      The development of shape memory materials to achieve recoverable high-strain capacities at high concentration of the crosslinker is still a great challenge due to their mutual exclusiveness. Here, slide-ring shape memory polymers (SMPs) with movable cross-links were prepared by varying the amount of the polyrotaxane cross-linkers. The slide-ring SMPs not only exhibit a combination of high strength and toughness, but also outstanding recoverable high-strain capacities and fast shape recovery. The elongation of the slide-ring SMPs at 1mol% crosslinker was as high as 881%, closer to physically cross-linked SMPs. As the growing deformation strain from 100% to 800%, the slide-ring SMPs still showed excellent shape memory performance with >90% shape fixity and shape recovery. The comparative analysis among movable cross-linking, chemical cross-linking and physical cross-linking SMPs in a different way revealed that the sliding effect of the polyrotaxane cross-linking is responsible for outstanding recoverable high-strain capacities of slide-ring SMPs. This design may provide a promising strategy for brittle shape memory materials to obtain high-strain capacities, such as epoxy resin and polylactic acid.

      PubDate: 2017-08-03T16:40:31Z
      DOI: 10.1016/j.reactfunctpolym.2017.07.002
  • Synthesis of sugar alcohol-derived water-soluble polyamines by the
           thiol-ene reaction and their utilization as hardeners of water-soluble
           bio-based epoxy resins
    • Authors: Mitsuhiro Shibata; Naomasa Ishigami; Ayaka Shibita
      Abstract: Publication date: Available online 22 July 2017
      Source:Reactive and Functional Polymers
      Author(s): Mitsuhiro Shibata, Naomasa Ishigami, Ayaka Shibita
      The allylation reactions of α,α′-diglycerol and d-sorbitol as sugar alcohols, and subsequent thiol-ene reactions with cysteamine hydrochloride produced a new water-soluble tetramine (N4DG) and hexamine (N6SB), respectively. The N4DG and N6SB were used as polyamine-type epoxy hardeners for water-soluble sugar alcohol-based epoxy resins, polyglycerol polyglycidyl ether (PGPE) and sorbitol polyglycidyl ether (SPE). The thermal and mechanical properties of the cured resins (PGPE-N4DG, PGPE-N6SB, SPE-N4DG, SPE-N6SB) were compared with those of the epoxy resins cured with a conventional water-soluble polyetheramine (PEA). Although 5% weight loss temperatures of the epoxy resins cured with N4DG and N6SB were lower than those of the PEA-cured resins, glass transition temperatures, tensile strengths and moduli of the former resins were much higher than those of the latter resins. Especially, SPE-N6SB exhibited the highest T g (22.8°C), tensile strength (43.6MPa) and modulus (990MPa) among all the cured resins.

      PubDate: 2017-07-23T16:16:04Z
      DOI: 10.1016/j.reactfunctpolym.2017.07.003
  • Adsorption of heavy metal ions by iminodiacetic acid functionalized D301
           resin: Kinetics, isotherms and thermodynamics
    • Authors: Fu-Qiang An; Rui-Yan Wu; Min Li; Tuo-Ping Hu; Jian-Feng Gao; Zhi-Guo Yuan
      Abstract: Publication date: Available online 22 July 2017
      Source:Reactive and Functional Polymers
      Author(s): Fu-Qiang An, Rui-Yan Wu, Min Li, Tuo-Ping Hu, Jian-Feng Gao, Zhi-Guo Yuan
      High adsorption capacity, fast adsorption rate, easy regeneration and good reusability were very important for qualified adsorbents used in removing toxic heavy metals from wastewater. Based on this, a novel adsorbent was well designed and synthesized by functionalizing D301 resin with iminodiacetic acid (IDA). The physicochemical characteristics of IDA-functionalized D301 (ID301) were characterized by the scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET), Fourier transform infrared spectroscopy (FTIR) and elemental analysis. The adsorption performances of ID301 towards toxic heavy metal ions were systematically performed from kinetics to isotherms and thermodynamics by batch technique. The effects of contact time, initial metal concentration, pH, temperature and adsorbent dosage on adsorption performance were investigated. ID301 possesses strong adsorption ability for Cu(II), Pb(II) and Cd(II). pH and temperature has a great influence on the adsorption capacity. The adsorption capacities of ID301 towards Cu(II), Pb(II) and Cd(II) could reach 4.48, 2.99 and 2.26mmol·g−1 at 293K and pH of 5, respectively. Langmuir isotherm and pseudo-second-order equation could satisfactorily describe the experimental data. The adsorption thermodynamic experiment indicated that adsorption of ID301 towards Cu(II), Pb(II) and Cd(II) was an endothermic and spontaneous chemisorption process drived by entropy. In addition, ID301 could be reused without losing adsorption capacity significantly.

      PubDate: 2017-07-23T16:16:04Z
      DOI: 10.1016/j.reactfunctpolym.2017.07.005
  • Editors and Editorial Board
    • Abstract: Publication date: August 2017
      Source:Reactive and Functional Polymers, Volume 117

      PubDate: 2017-07-12T15:34:41Z
  • Chemical modification of PET surface and subsequent graft copolymerization
           with poly(N-isopropylacrylamide)
    • Authors: Parisa Golshaei; Olgun Güven
      Abstract: Publication date: Available online 29 June 2017
      Source:Reactive and Functional Polymers
      Author(s): Parisa Golshaei, Olgun Güven
      Thermo-sensitivity has been introduced onto poly(ethylene terephthalate) (PET) surfaces by graft copolymerization of N-isopropylacrylamide (NiPAAm). The PET surface was first photo-oxidized in the presence of H2O2, to have enriched concentration of COOH groups which were later reacted with allylamine (AlAm) to introduce vinyl end groups at the surface. These groups were used as active sites for thermally initiated graft copolymerization of NiPAAm. The influence of solvent, monomer concentration and time on grafting has been investigated. Spectroscopic analysis confirmed the presence of (AlAm) linked to treated surfaces as well as poly(NiPAAm) grown from them. The thickness of grafted layer can be adjusted between 10 and 18μm via grafting degree by controlling of grafting reaction parameters. Imaging in water environment revealed the reversible modification of surface morphology below and above the lower critical solution temperature (LCST) of PNiPAAm. The grafted surfaces were analyzed by colorimetric assay, ATR-FTIR, Raman, and XPS spectroscopies and Thermogravimetric analysis (TGA), and Differential scanning calorimetry (DSC).
      Graphical abstract image

      PubDate: 2017-07-02T13:50:24Z
      DOI: 10.1016/j.reactfunctpolym.2017.06.015
  • Surface properties and morphology of selected polymers and their blends
           designed to mucoadhesive dosage forms
    • Authors: A. Bartkowiak; M. Rojewska; A. Biadasz; J. Lulek; K. Prochaska
      Abstract: Publication date: Available online 12 June 2017
      Source:Reactive and Functional Polymers
      Author(s): A. Bartkowiak, M. Rojewska, A. Biadasz, J. Lulek, K. Prochaska
      In the mucoadhesive drug delivery systems the controlling mechanism is initiated by the wetting and swelling of the polymer matrix. In view of the above, the aim of our study was to analyze the effect of model saliva and gastric fluids on the wetting properties and sorption of selected mucoadhesive (Carbopol 974P NF, HEC) and film-forming (Kollidon VA 64) polymers as well as their blends. We considered two types of examined materials: individual polymers and their blends in the form of powders as well as in the form of compressed discs (blanc tablets). The contact angle measurements for powders were performed according to the Washburn method, using the capillary rise technique, whereas the sessile drop method was applied to the compressed discs of mucoadhesive polymers. The surface energy was determined by the OWRK method. The influence of composition of the polymer blends and pH of model fluids on the wetting properties and sorption of the polymer formulations was evaluated. Moreover, significant differences in the morphology, surface roughness and surface properties of mucoadhesion polymers considered were discussed.

      PubDate: 2017-06-16T12:45:19Z
      DOI: 10.1016/j.reactfunctpolym.2017.06.011
  • Carboxymethyl-β-cyclodextrin grafted chitosan nanoparticles as oral
           delivery carrier of protein drugs
    • Authors: Mingming Song; Liangping Li; Yue Zhang; Kuanmin Chen; Hui Wang; Renmin Gong
      Abstract: Publication date: Available online 22 May 2017
      Source:Reactive and Functional Polymers
      Author(s): Mingming Song, Liangping Li, Yue Zhang, Kuanmin Chen, Hui Wang, Renmin Gong
      In this paper, the novel carboxymethyl-β-cyclodextrin grafted chitosan (CMCD-g-CS) nanoparticles were fabricated and their potential as oral delivery carrier of protein drugs was evaluated. The physicochemical properties of the prepared nanocarriers were characterized by Fourier transforms infrared spectroscopy, nuclear magnetic resonance, transmission electron microscopy and dynamic light scattering. Bovine serum albumin (BSA), a model protein drug, was loaded in prepared nanocarriers with ideal entrapment efficiency (EE) and loading content (LC). The drug release profiles of BSA loaded nanoparticles were studied in simulated gastric fluid (SGF), simulated intestinal fluid (SIF) and simulated colonic fluid (SCF). It was found that the drug loaded nanovehicles displayed a typical controlled sustained release profiles and the amount of BSA released from the nanocarriers was much higher in SIF and SCF than it in SGF. The research results suggested that the CMCD-g-CS nanoparticles had the potential as promising nanocarriers for oral delivery of protein drugs.

      PubDate: 2017-05-23T08:04:15Z
      DOI: 10.1016/j.reactfunctpolym.2017.05.008
  • Compatibility confirmation and refinement of thermal and mechanical
           properties of poly (lactic acid)/poly (ethylene-co-glycidyl methacrylate)
           blend reinforced by hexagonal boron nitride
    • Authors: Ashish Kumar; T. Venkatappa Rao; S. Ray Chowdhury; S.V.S. RamanaReddy
      Abstract: Publication date: Available online 19 May 2017
      Source:Reactive and Functional Polymers
      Author(s): Ashish Kumar, T. Venkatappa Rao, S. Ray Chowdhury, S.V.S. RamanaReddy
      The formation of PLA/PEGM graft copolymers during the melt blending of poly (lactic acid) (PLA) and poly (ethylene-co-glycidyl methacrylate) (PEGM) act as an interface between two polymer matrices was illustrated by the epoxide ring-opening mechanism. There are two coupling reaction mechanisms of glycidyl methacrylate (GM) unit of PEGM with the terminal groups of PLA. The analysis of FTIR and 1H NMR spectra elucidates the chemical reaction of GM unit of PEGM with carboxylic and hydroxyl terminal groups of PLA. FTIR analysis also confirms that the carboxylic terminal groups of PLA are more likely to react with GM group of PEGM. Hence, PLA grade having carboxyl terminal groups is more compatible with PEGM as compared to the PLA grade having hydroxyl and ester terminal groups. The hexagonal boron nitride(HBN) is incorporated with various labels such that 1phr, 5phr and 10phr to prepare PLA/PEGM/HBN blend-composites. The blend-composite with low HBN content i.e. 1phr shows better mechanical and thermal properties than neat PLA, PLA/PEGM blend and other blend-composites. This is attributed to the formation of covalent bond between polymer chains and HBN crystal layers and also due to the intermolecular interaction between the hydrogen atoms of polymer chains with the nitrogen atoms of HBN, which is confirmed by the FTIR and 1H NMR studies. TG/DTG, SEM, XRD analysis and the improvement in the mechanical and thermal properties of the prepared blend also asserts the interfacial compatibility between PLA and PEGM in the blend and chemical interaction of HBN particles with polymer matrix.
      Graphical abstract image

      PubDate: 2017-05-23T08:04:15Z
      DOI: 10.1016/j.reactfunctpolym.2017.05.005
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Heriot-Watt University
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